Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019214 (hepatosplenomegaly)
 4,408 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sialidosis is an autosomal recessive disease caused by the genetic deficiency of lysosomal sialidase, which catalyzes the catabolism of sialoglycoconjugates. The disease is associated with progressive impaired vision, macular cherry-red spots, and myoclonus (sialidosis type I) or with skeletal dysplasia, Hurler-like phenotype, dysostosis multiplex, mental retardation, and hepatosplenomegaly (sialidosis type II). We analyzed the effect of the missense mutations G68V, S182G, G227R, F260Y, L270F, A298V, G328S, and L363P, which are identified in the sialidosis type I and sialidosis type II patients, on the activity, stability, and intracellular distribution of sialidase. We found that three mutations, F260Y, L270F, and A298V, which are clustered in the same region on the surface of the sialidase molecule, dramatically reduced the enzyme activity and caused a rapid intralysosomal degradation of the expressed protein. We suggested that this region might be involved in sialidase binding with lysosomal cathepsin A and/or beta-galactosidase in the multienzyme lysosomal complex required for the expression of sialidase activity. Transgenic expression of mutants followed by density gradient centrifugation of cellular extracts confirmed this hypothesis and showed that sialidase deficiency in some sialidosis patients results from disruption of the lysosomal multienzyme complex.
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PMID:Mutations in sialidosis impair sialidase binding to the lysosomal multienzyme complex. 1127 74

The lysosomal storage disorder, mucopolysaccharidosis type I (MPS I), is caused by a deficiency of the enzyme alpha-L-iduronidase, which is involved in the breakdown of dermatan and heparan sulphates. There are three clinical phenotypes, ranging from the Hurler form characterised by skeletal abnormalities, hepatosplenomegaly and severe mental retardation, to the milder Scheie phenotype where there is aortic valve disease, corneal clouding, limited skeletal problems, but no mental retardation. In this study, 85 MPS I families (73 Hurler, 5 Hurler/Scheie, 7 Scheie) were screened for 9 known mutations (Q70X, A75T, 474-2a>g, L218P, A327P, W402X, P533R, R89Q, 678-7g>a). W402X was the most frequent mutation in our population (45.3%) and Q70X was the second most frequent (15.9%). In 30 families, either one or both of the mutations were not identified, which accounted for 25.9% of the total alleles. Therefore, all 14 exons of the alpha-L-iduronidase gene were screened in these patients and 23 different sequence changes were found, 17 of which were previously unknown. The novel sequence changes include 4 deletions (153delC, 628del5, 740delC, 747delG), 5 nonsense mutations (Q60X, Y167X, Q400X, R619X, R628X), 6 missense mutations (C205Y, G208V, H240R, A319V, P496R, S633L), a splice site mutation (IVS12+5g>a), and a rare polymorphism (A591T). The polymorphism and novel missense mutations were transiently expressed in COS-7 cells and all of them except the polymorphism showed complete loss of enzyme activity. In total, 165 of the 170 mutant alleles were identified in this study and despite the high frequency of W402X and Q70X, the identification of many novel mutations unique to individual families further highlights the genetic heterogeneity of MPS I.
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PMID:Mutational analysis of 85 mucopolysaccharidosis type I families: frequency of known mutations, identification of 17 novel mutations and in vitro expression of missense mutations. 1173 25

Ichthyosis follicularis (IF) is a very rare neurocutaneous, X-linked recessive condition affecting the skin, hair, eyes, and central nervous system (CNS). This report describes a child with facial dysmorphism, mental retardation, psychomotor delay, congenital alopecia of the scalp, eyebrows, and eyelashes, and extensive spiny follicular papules. A skin biopsy specimen showed the characteristic absence of sebaceous glands. We also reviewed the literature on this very rare entity. Additional findings observed in our patient, including hepatosplenomegaly, undescended testicles, and ptosis, have not been reported before.
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PMID:Ichthyosis follicularis: a case report and review of the literature. 1255 47

Zimmermann-Laband syndrome (ZLS) is a rare disorder characterized by gingival fibromatosis, abnormalities of the nose and/or ears, and absence or hypoplasia of nails or terminal phalanges of hands and feet. Other more variable features include hyperextensibility of joints, hepatosplenomegaly, mild hirsutism, and mental retardation. The genetic basis of ZLS is unknown; autosomal dominant inheritance has been suggested. We report an apparently balanced chromosomal aberration, 46,XX, t(3;8)(p13-p21.2;q24.1-q24.3), in a family with an affected mother and daughter. Using fluorescence in situ hybridization with BAC clones, we refined the breakpoints to 3p21.2 and 8q24.3 and, thereby, narrowed down both breakpoint regions to approximately 1.5 Mb. Our data provide additional support to the assumption that ZLS follows autosomal dominant inheritance. The 3;8 translocation described here represents a powerful resource to identify the causative gene for ZLS that maps most likely to one of the breakpoints.
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PMID:Zimmermann-Laband syndrome associated with a balanced reciprocal translocation t(3;8)(p21.2;q24.3) in mother and daughter: molecular cytogenetic characterization of the breakpoint regions. 1259 95

We present a case of alpha-mannosidosis with its mutational analysis. She was referred to our hospital with the provisional diagnosis of mucolipidosis. She was the first child of second-degree relative parents. She had a coarse face with flat and wide nasal bridge, hepatosplenomegaly, umbilical hernia, lumbar gibbus, motor and mental retardation and deafness. On peripheral blood smear, lymphocytes revealed vacuoles and neutrophils contained some granules resembling Reilly bodies seen in mucopolysaccharidosis (MPS). Based on these findings, the diagnosis of alpha-mannosidosis was suspected. Her urine oligosaccharide chromatography showed an abnormal pattern with a heavy trisaccharide band. Enzyme studies on white cells confirmed a deficiency of alpha-mannosidase activity, which was 2.6 micromol/g/hr. Her DNA analysis showed a S453Y mutation.
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PMID:Alpha-mannosidosis and mutational analysis in a Turkish patient. 1271 72

Lysosomal sialidase (EC 3.2.1.18) has a dual physiological function; it participates in intralysosomal catabolism of sialylated glycoconjugates and is involved in cellular immune response. Mutations in the sialidase gene NEU1, located on chromosome 6p21.3, result in autosomal recessive disorder, sialidosis, which is characterized by the progressive lysosomal storage of sialylated glycopeptides and oligosaccharides. Sialidosis type I is a milder, late-onset, normosomatic form of the disorder. Type I patients develop visual defects, myoclonus syndrome, cherry-red macular spots, ataxia, hyperreflexia, and seizures. The severe early-onset form, sialidosis type II, is also associated with dysostosis multiplex, Hurler-like phenotype, mental retardation, and hepatosplenomegaly. We summarize information on the 34 unique mutations determined so far in the sialidase gene, including four novel missense and one novel nonsense mutations found in two Czech and two French sialidosis patients. The analysis of sialidase mutations in sialidosis revealed considerable molecular heterogeneity, reflecting the diversity of clinical phenotypes that make molecular diagnosis difficult. The majority of sialidosis patients have had missense mutations, many of which have been expressed; their effects on activity, stability, intracellular localization, and supramolecular organization of sialidase were studied. A structural model of sialidase allowed us to localize mutations in the sialidase molecule and to predict their impact on the tertiary structure and biochemical properties of the enzyme.
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PMID:Molecular pathology of NEU1 gene in sialidosis. 1451 45

This report concerns congenitally Na(+)-K(+) leaky red cells of the 'hereditary stomatocytosis' class. Three new isolated cases and one new pedigree are described, and one previously reported case is expanded. In all cases, Western blotting of red cell membranes revealed a deficiency in the 32 kDa membrane protein, stomatin. All showed pronounced cation leaks at 37 degrees C with markedly abnormal intracellular Na(+) and K(+) concentrations, like all other such stomatin-deficient cases. Consistent with recent findings in two previously described British pedigrees, immunocytochemistry demonstrated that the deficiency of stomatin was not complete. On typical blood films, some red cells showed positive stomatin immunoreactivity, while most were negative, although in one case only a minority were negative. All platelets and neutrophils were stomatin positive. The cases differed markedly between themselves with regard to the temperature dependence of the passive leak to K(+). Three showed a simple monotonic temperature dependence, while two showed a minimum at around 20-25 degrees C, such that the cells were extremely leaky at 0 degrees C, giving the phenotype known as 'cryohydrocytosis'. These patients are the only two known cases of stomatin-deficient cryohydrocytosis. Both showed a congenital syndrome of mental retardation, seizures, cataracts and massive hepatosplenomegaly, probably defining a new haemato-neurological syndrome.
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PMID:Four new cases of stomatin-deficient hereditary stomatocytosis syndrome: association of the stomatin-deficient cryohydrocytosis variant with neurological dysfunction. 1518 Aug 70

The case report describes a young boy with renal, retinal, hepatic and cerebellar involvement in a rare syndrome. He had polyuria, deranged renal functions and cystic lesions in kidneys, which led to the diagnosis of nephronophthisis (NPH). Extra-renal involvement with night blindness, truncal ataxia, mental retardation and hepatosplenomegaly. Thus, every patient with NPH should be carefully examined for extra-renal involvement.
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PMID:Nephronophthisis: a variant. 1592 46

alpha-Mannosidosis is a rare lysosomal storage disease that is caused by an inherited deficiency of the lysosomal alpha-mannosidase. Clinical symptoms include coarse facial features, skeletal involvement (dysostosis multiplex), hearing disabilities, mental retardation and hepatosplenomegaly. Only few cases with ocular symptoms have been reported, mainly with lenticular opacities. We report on two brothers with complex neurological symptoms who presented with late-onset retinal dystrophy and were followed up for 6 years.
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PMID:Late-onset retinal dystrophy in alpha-mannosidosis. 1607 19

Zimmermann-Laband syndrome (ZLS) is an autosomal dominant disorder characterized by gingival fibromatosis, absent or dysplastic distal phalanges, vertebral defects, hepatosplenomegaly, hypertrichosis and sometimes mental retardation. We describe two unrelated patients, a girl aged 9 years and a boy 11 months whose clinical and radiological findings permit us to diagnose the ZLS. Body overgrowth, present in both patients, was identified as a main clinical feature not previously reported as well as the presence in neuroimaging studies of a cavernous hemangioma on the frontal and the left cerebellar regions in the boy. The girl also presented important radiological characteristics such as broad medulary canals and metaphyses of long bones, thin cortices, broad ribs, accelerated skeletal maturation as well as high intelligence level. A wide clinical spectrum in ZLS is also considered.
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PMID:Zimmermann-Laband syndrome: further clinical delineation. 1626 93


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